EPON boasts symmetrical downlink and uplink transmission capacities of 1. 25G upstream and downstream, and is widely used in the optical access network based on Ethernet. EPON modules are divided into classes PX10 and PX20, with specific parameters as follows: With the. EPON provides fixed uplink and downlink 1. According to actual needs, the uplink and downlink. GPON: GPON supports a variety of data rate levels, which can support asymmetric uplink and downlink rates, downlink 2. 25 Gbps, and wavelengths of 1490 nm and 1310 nm, respectively.